<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <!-- 访问 object 中的属性，将所有属性为val的全部相乘并输出 -->
    <script>
        var obj = {
            name: '小明',
            age: 19
        }
        var obj1 = {
            name: '小陈',
            age: 20
        }
        for (var arr in obj) { };
        for (var arr1 in obj1) { };
        var html = obj[arr] * obj1[arr1];
        console.log(html);
    </script>
</body>

</html>